Boat construction



March 19, 1940. QSVAN D 2,193,892

BOAT CONSTRUCTION Filed Feb. 17, 1938 CLYDE 5. VAN GORDEN Patented Mar. 19, 1940 UNITED STATES PATENT OFFICE 4 Claims.

The present invention is in general concerned with an improved boat construction and is in particular concerned with an inexpensive,lightweight construction which isparticularly adapt- 5 ed for small boats such as rowboats and boats utilizing an outboard motor.

To thisend, it is a primary object of the pres ent invention to provide a boat construction in which a laminated plywood material may be uti- 10 lized, whereby the weight may be decreased without sacrifice in the strength of the materials used heretofore for such purpose.

A further object of the invention is to provide an improved bottom construction whereby a 15 streamlined bottom at the bow of the boat may be secured.

A further object of the invention is to provide an improved bottom construction which will permit the use of a single sheet-of flexible material 20'to be used and secured to a framework in such manner as to produce curved bottom lines which are particularly advantageous when the boat is utilized with an outboard motor.

Another object of the invention is to provide 25 an improved bottom construction which will prevent the boat from skidding.

In accordance with the general features of the herein described invention, it is proposed to provide a boat of the herein described type which 30 will have a streamlined bow portion on the bottom, a flat bottom portion substantially amidships and a fluted bottom at the stern of the boat to prevent skidding.

One of the specific features resides in the man-.

35 ner in which the bottom is streamlined at the bow. The bowTend of the bottom member is provided with a V cut-out portion with the apex of the V disposed towards the stern. The bottom member is initially fiat, but when the edges of the V are brought together and secured in place, the material will assume a curvature. The

joint formed by the abutting edges of the V outout is covered by the keel.

At the stem, the end edge is secured to a frame 45 member having a bottom edge which is curved will more readily appear from the following detailed descriptiontaken in connection with the accompanying drawing which illustrates a single embodiment thereof, and in which:

- Figure 1 is a plan view of a boat of the herein described type embodying the features and advantages of the present invention;

Figure 2 is an isometric view showing the boat overturned, whereby the curved bow and stern groove flutes in the bottom are disclosed;

Figure 3 shows the bottom construction before it is secured in place;

Figure 4 is an enlarged fragmentary detailed View partly in section showing the manner in which the bottom and planking are secured to the stem;

Figure 5 is an enlarged fragmentary sectional View taken through the stem substantially on line V-V of Figure 4; and

Figure 6 is an enlarged sectional view taken through the stern of the boat substantially on line VIVI of Figure 1 to show the details of construction of the sternframework.

As shown on the drawing:

As shown in Figure 1, the general shape of the boat from stem to stern is determined by a skeleton framework construction. This framework comprises elongate side members l0 and II which are interconnected in the midship area by transversely extending ribs l2, l3 and M having their ends respectively secured in any appropriate manner to the side frame members.

These side members are inwardly bowed at the bow portion and disposed in abutting relation at their ends with a triangular shaped stem 15 which is disposed with its base portion towards the .stern and its apex forwardly pointing. The stem is also forwardly inclined a slight amount as clearly shown in Figure 4.

At the stern end of the boat is provided an end section comprising a bottom member l6 which extends transversely of the boat and is connected in any suitable manner at its ends to the lateral frame members l0 and II. Upright corner members I! and I8 are provided, these members being respectively secured at their lower ends to the ends of member I 6. Intermediate the corner members I! and I8 is a stern post 19 having its lowermost end secured to the member l6 intermediate its ends. This stern post forms a support for an outboard motor, generally indicated at 20 which may be removably clamped in the usual manner to the stern post.

The frame member 16 has its lowermost edge curved to form a substantially M shaped bottom.

In other words, there is formed on either side of the midpoint of member I6 a concave curved edge as shown at 2| and 22.

Suitable thwarts 23 and 24 are provided, and, of course, any number of thwarts may be provided although in the present instance only two are shown, these being indicated at 23 and 24. These thwarts are supported at their ends by vertical members which raise the thwarts above the bottom of the boat and are secured at their lower ends to the side frame members I0 and II in any suitable manner.

As shown in Figure 3, the bottom plank is of one piece construction, this plank being generally indicated by the numeral 25. Although any light material may be utilized, it is preferred to use a laminated plywood in which the laminations are bound together by a water-proof glue composition so as to produce a waterproof structure which is light of weight but very strong. This material is somewhat flexible and can be bent to readily conform to a curved surface.

Advantage is taken of this fact to secure lines in the bottom which will increase the stability of the boat and enable streamlining.

The bottom plank is at its lateral edges cut to conform to the general shape of the boat and at its bow portion is provided with a V-shaped slot 26 whichextends from the forward end edge of the plank with its edges 21 and 28 converging to a point 29 which may be substantially onethird of the length of the boat from the bow.

The plank is secured in position to the framework by means of suitable screws 30 which extend through the marginal edges of the plank into the lateral frame members. The V notch of the bottom is so proportioned that when the edges 21 and 28 are brought together into abutting relation, as shown at 3| in Figure 5, the bottom will form an'upwardly extending curve as indicated in Figure 4.

At the stern, the end edge of the bottom member is secured to the lowermost edge of mem ber |6.

The seeming of this edge causes it to conform to the curves 2| and 22 and set up distorting forces in the adjacent bottom material of such character, as to produce forwardly extending flutes or grooves 32 and 33 which are gradually decreased in width as well as depth and terminate in the flat undeformed bottom portion amidships. These grooves preferably extend from the stern forwardly for a distance substantially equal to one-third of the boat length. The portion 34, as shown in Figure 2, is of flat construction and interconnects the curved bow and fluted stern. However, these grooves may be made of greater or less length as desired, simply by increasing or decreasing the depth of the curves 2| and 22.

. The joint formed by the edges 21 and 28 at the bow end of the bottom is covered and prevented from leaking by means of a longitudinal extending keel member 35 which is connected at its bow end to the stem l5 and at its stem end to member Is, this latter end of the keel being disposed between the two flutes or grooves 32 and 33.

Side members 36 and 3'? which are each of unitary plank construction are provided. These members are likewise constructed of plywood and are secured along their lowermost edges to the associated lateral frame members. At the how end each plank extends into a groove in the stem, the plank 37 extending into a groove 38 and the plank 36 into a groove 39. These grooves extend longitudinally of the stem and open into the base portion thereof. The ends of the planks may be secured as by screws 40 to the stem.

At the stem, the plank ends are secured to the corner members I! and I8 respectively. The stern end of the boat is closed by a transom 4| which may be secured at'its ends to corner members l1 and I8 and intermediate its ends to the stern post l9. Along the bottom, the transom is secured to member |6.

While I have described a specific frame structure, it is to be understood that the frame structure may be variously modified to meet different conditions as to shape and size of the boat.

In my disclosure, the bow is shown as being provided with a forward deck 42 which extends between the tops of the 'side planking and which, if desired, may be provided with a slight upward curvature.

The upper edges of the side planking, in accordance with the usual practice, are provided with a rubbing bead or strake 43.

From the foregoing description, it will be apparent that the present invention provides an improved boat construction which is inexpensive to manufacture, light in weight, but strong and durable; which embodies an improved bow construction; which incorporates a stern construction having flutes or grooves on either side of the keel for preventing skidding, particularly when used with an outboard motor; and which is especially adapted to be constructed from a waterproof laminated plywood.

Now, it is, of course, to be understood that although I have described in detail a single embodiment of my invention, the invention is not to be thus limited but only insofar as defined by the scope and spirit of the appended claims.

I claim as my invention:

1. In a boat construction, a transversely extending stern strip having its lower edge inwardly curved between each end and the central portion thereof, the end and central portions of said edge lying substantially in the same plane, an initially flat bottom member of waterproof plywood material, means for securing the stem end edge margin of the bottom member to said strip against the lower edge thereof, the securement of the stern edge margin of the bottom member to the stern strip conforming the said edge margin to the lower edge of the stern strip and effecting forwardly extending stern flutes of decreasing depth without preformation of the bottom member, and a keel strip secured to the outer surface of the bottom member and extending between said bottom flutes.

2. A boat construction comprising a stern member having a lowermost edge surface undulated in a direction extending transversely of the boat, a one-piece initially flat bottom member of plywood, means for securing and conforming the stern end edge margin only of the bottom member against the undulated edge surface of the stern member, whereby the bottom material adjacent the stern edge margin is forced to assume a natural curvature and form flutes extending from said end margin towards the bow end of the boat, without preforming the bottom member.

3. A boat construction comprising a one-piece stem member of substantially triangular transverse cross-section having its apex forming edge disposed forwardly, a transversely extending stern frame including upright side pieces and a ternal central keel strip extending the full bottom piece, said bottom piece being shaped to present a relatively flat substantially M-shaped undersurface, boat sides each formed of a single plank, the forward ends of said planks being rabbeted in said stem and the other ends respectively secured to the side pieces of the stern frame, an initially flat one-piece bottom member of waterproof plywood material having a central V-cut-out at its forward end extending substantially one-third the length of the bottom member, said bottom member being deformed to effect a longitudinally extending curvature in the bottom member in the area containing said cut-out by disposing the edges of the V in abutting relation; and deformed at its stern end to form flutes on either side of the bottom center line by conforming this end of the bottom to the under surface of the stern frame bottom piece, said flutes extending forwardly substantially onethird the bottom length, the intermediate bottom portion between the V-cut-out and said flutes being substantially flat and undeformed, an exlength of said bottom member over the abutting edges of the V-cut-out and between said flutes at the stern, and means securing the peripheral edge of the bottom member, to said stern, side planks and stem frame bottom piece.

4. A boat construction comprising a stern member having a lowermost edge surface extending transversely of the longitudinal center line of the boat and curved upwardly towards the center line, a one-piece initially fiat bottom member of plywood, means for securing and conforming the stern end edge margin only of the bottom member against the curved edge of the stern member, whereby the bottom material adjacent the stern edge margin is forced to assume a natural curvature and form a flute extending from said margin towards the bow end of the boat, without preforming the bottom member.

CLYDE S. VAN GORDEN. 

